Earth exploration is engaged in geology and geophysics. These sciences are interconnected with each other. Geophysics studies the mantle, crust, external liquid and internal solid core. The discipline explores the oceans, surface and groundwater. This science also studies the physics of the atmosphere. In particular, aeronomy, climatology, meteorology. What is geology? Within the framework of this discipline, slightly different studies are carried out. Next, find out what geology is studying.
General information
General geology is a discipline in which the structure and patterns of development of the Earth, as well as other planets related to the solar system, are studied. In addition, this applies to their natural companions. General geology is a complex of sciences. The study of the Earth’s structure is carried out using physical methods.
Main directions
There are three of them: historical, dynamic and descriptive geology. Each direction is distinguished by its basic principles, as well as research methods. Next, we consider them in more detail.
Descriptive Direction
It studies the placement and composition of the corresponding bodies. In particular, this applies to their shapes, sizes, relationships and sequence of occurrence. In addition, this area deals with the description of rocks and various minerals.
Process Evolution Research
This is the dynamic direction. In particular, the processes of rock destruction, their movement by the wind, underground or ground waves, and glaciers are investigated. This science also considers internal volcanic eruptions, earthquakes, the movement of the earth's crust and the accumulation of precipitation.
Chronological order
Speaking about what geology studies, it should be said that research does not only apply to phenomena that occur on Earth. One of the areas of discipline analyzes and describes the chronological order of processes on Earth. These studies are carried out within the framework of historical geology. The chronological order is organized in a special table. It is better known as the geochronological scale. It, in turn, is divided into four intervals. This was done in accordance with stratigraphic analysis. The first interval covers the following period: the formation of the Earth - the present. Subsequent scales reflect the last segments of the previous. They are marked with stars on an enlarged scale.
Features of absolute and relative age
Studying the geology of the Earth is critical to humanity. Thanks to research, the age of the Earth, for example , has become known. Geological events are assigned an exact date that refers to a specific point in time. In this case, we are talking about absolute age. Events can also be assigned to certain intervals of the scale. This is relative age. Speaking about what geology is, it should be said that in the first place it is a whole complex of scientific research. Within the discipline, various methods are used to determine the periods to which specific events are tied.
Radioisotope dating method
It was opened at the beginning of the 20th century. This method provides an opportunity to determine the absolute age. Before its discovery, geologists were very limited. In particular, only relative dating methods were used to determine the age of the relevant events. Such a system is able to establish only a sequential order of recent changes, and not the date of their implementation. However, this method is still very effective. This applies when materials devoid of radioactive isotopes are available.
Comprehensive study
Comparison of a particular stratigraphic unit with another occurs due to the layers. They consist of sedimentary and rock formations, fossils and surface deposits. In most cases, the relative age is determined using the paleontological method. At the same time, the absolute is mainly based on the chemical and physical properties of rocks. As a rule, this age is determined by radioisotope dating. This refers to the accumulation of decay products of the corresponding elements that are part of the material. Based on the data obtained, an approximate date of occurrence of each event is established. They are located at certain points on the overall geological scale. To build the exact sequence, this factor is very important.
Main sections
Briefly answering the question of what geology is, is quite difficult. It should be noted here that science includes not only the above areas, but also various groups of disciplines. At the same time, the development of geology continues today: new branches of the scientific system appear. Existing and emerging new groups of disciplines are associated with all three areas of science. Thus, there are no exact boundaries between them. What geology studies is, to one degree or another, investigated by other sciences. As a result, the system comes into contact with other areas of knowledge. There is a classification of the following groups of sciences:
- Applied disciplines.
- About the Earth's crust.
- On modern geological processes.
- On the historical sequence of relevant events.
- Regional geology.
Mineralogy
What does geology study in this section? Studies concern minerals, their genesis, and classification. Lithology deals with the study of rocks that were formed in processes associated with the hydrosphere, biosphere and Earth's atmosphere. It is worth noting that they are still inaccurately called sedimentary. Geocryology is studying a number of characteristic features and properties that acquire permafrost rocks. Crystallography was originally one of the areas of mineralogy. At present, it can most likely be attributed to physical discipline.
Petrography
This section of geology studies metamorphic and igneous rocks mainly from a descriptive side. In this case, we are talking about their genesis, composition, texture features and classification.
The earliest section of geotectonics
There is a direction that deals with the study of violations of the earth's crust and the forms of occurrence of the corresponding bodies. Its name is structural geology. I must say that as a science, geotectonics appeared at the beginning of the XIX century. Structural geology investigated medium and small scale tectonic dislocations. Size - tens to hundreds of kilometers. This science was finally formed only by the end of the century. Thus, there was a transition to the allocation of tectonic units of global and continental scale. In the future, the doctrine gradually grew into geotectonics.
Tectonics
This section of geology studies the movement of the earth's crust. It also includes the following areas:
- Experimental tectonics.
- Neotectonics.
- Geotectonics.
Narrow sections
- Volcanology. A rather narrow section of geology. He is studying volcanism.
- Seismology. This section of geology studies the geological processes that occur during earthquakes. This also includes seismic zoning.
- Geocryology. This section of geology focuses on the study of permafrost.
- Petrology. This section of geology studies the genesis as well as the conditions of origin of metamorphic and igneous rocks.
Process flow
Everything that geology studies contributes to a better understanding of various processes on earth. For example, the chronology of events is a critical subject. After all, every geological science is historical in varying degrees. They consider existing formations precisely from this point of view. First of all, these sciences figure out the sequence of formation of modern structures.
Classification of periods
The entire history of the Earth is divided into two major stages, which are called aeons. Classification is in accordance with the appearance of organisms with solid parts that leave traces in sedimentary rocks. According to paleontology, they allow you to determine the relative geological age.
Subjects of research
Phanerozoic began with the advent of fossils on the planet. Thus, an open life developed. This period was preceded by Precambrian and cryptose. There was a hidden life at this time. Precambrian geology is considered a special discipline. The fact is that she studies specific, mainly repeatedly and strongly metamorphous complexes. In addition, it is characterized by special research methods. Paleontology focuses on the study of ancient life forms. She describes the fossils and traces of the life of organisms. Stratigraphy determines the relative geological age of sedimentary rocks and the separation of their thicknesses. She also deals with the correlation of various formations. Paleontological definitions are a source of data for stratigraphy.
What is applied geology
Some areas of science in one way or another interact with others. However, there are disciplines that are located on the border with other branches. For example, the geology of minerals. This discipline deals with the methods of search and exploration of rocks. It is divided into the following types: geology of coal, gas, oil. There is also metallogeny. Hydrogeology focuses on the study of groundwater. There are a lot of disciplines. All of them are of practical importance. For example, what is engineering geology? This section deals with the study of the interaction of structures and the environment. Soil geology is in close contact with it, since, for example, the choice of material for building construction depends on the composition of the soil.
Other subtypes
- Geochemistry. This section of geology focuses on the study of the physical properties of the Earth. It also includes a set of exploration methods, among them electrical exploration of various modifications, magnetic, seismic and gravity exploration.
- Geobarothermometry. This science is studying a set of methods for determining the temperature and pressure of formation of rocks and minerals.
- Microstructural geology. This section deals with the study of rock deformation at the micro level. The scale of aggregates and grains of minerals is implied.
- Geodynamics. This science focuses on the study of processes on a planetary scale that occur as a result of the evolution of the planet. The relationship of mechanisms in the earth's crust, mantle and core is studied.
- Geochronology. This section deals with the determination of the age of minerals and rocks.
- Lithology. It is also called petrography of sedimentary rocks. Engaged in the study of relevant materials.
- History of geology. This section focuses on the totality of information received and the ore business.
- Agrogeology. This section is responsible for the search, production and use of agricultural ore for agricultural purposes. In addition, he studies the mineralogical composition of soils.
The following geological sections are concentrated on the study of the solar system:
- Cosmology
- Planetology.
- Cosmic geology.
- Cosmochemistry
Mountain geology
It is differentiated by types of mineral raw materials. There is a division into the geology of non-metallic and ore useful rocks. This section is devoted to the study of the patterns of distribution of the corresponding deposits. Their relationship with the following processes is also established: metamorphism, magmatism, tectonics, sedimentation. Thus, an independent branch of knowledge appeared, which is called metallogeny. The geology of non-metallic minerals is also subdivided into the science of combustible substances and caustobiolites. This includes shale, coal, gas, oil. The geology of non-combustible rocks includes building materials, salts and much more. Also included in this section is hydrogeology. It is dedicated to groundwater.
Economic direction
It is a fairly specific discipline. She appeared at the intersection of economics and geology of minerals. This discipline focuses on the valuation of subsurface sites and deposits. The term "mineral", given this, can be more likely attributed to the economic sphere than to the geological one.
Intelligence Features
The geology of the deposit is an extensive scientific complex, within the framework of which measures are carried out to determine the industrial significance of the areas of occurrence of rocks that have received a positive assessment based on the results of prospecting and evaluation activities. During exploration, the installation of geological and industrial parameters. They, in turn, are necessary for an appropriate assessment of sites. This also applies to the processing of recoverable minerals, the provision of operational measures, and the design of the construction of mining enterprises. Thus, the morphology of the bodies of the corresponding materials is determined. This is very important for choosing a system for the subsequent processing of minerals. The installation of the contours of their bodies. In this case, geological boundaries are taken into account. In particular, this refers to the surface of faults and contacts of lithologically different rocks. Also, the nature of the distribution of minerals, the presence of harmful impurities, and the content of associated and main components are recorded.
Upper horizons of the crust
Their study is engaged in engineering geology. Information obtained during the study of soils provides the opportunity to determine the suitability of the relevant materials for the construction of specific objects. The upper horizons of the earth's crust are often called the geological environment. The subject of this section is information about its regional features, dynamics and morphology. The interaction with engineering structures is also being studied. The latter are often referred to as elements of the technosphere. At the same time, the planned, current or carried out economic activities of a person are taken into account. Engineering and geological assessment of the territory involves the allocation of a special element, which is characterized by homogeneous properties.
A few basic principles
The above information allows you to clearly understand what geology is. It is necessary to say that science is considered historical. She has many important tasks. First of all, it concerns the determination of the sequence of geological events. For the high-quality fulfillment of these tasks, a number of intuitively regular and simple features relating to the temporal ratio of rocks have long been developed. Intrusive relationships are contacts of the corresponding rocks and their thicknesses. All conclusions are made on the basis of detected signs. Relative age allows you to determine secant relationships. For example, if it breaks rocks, this allows us to conclude that the fault was formed later than them. The principle of ensuring continuity is that the building material from which the layers are formed can be stretched over the surface of the planet in the event that it is not limited by some other mass.
Historical information
The first observations are usually attributed to dynamic geology. In this case, we mean information about the movement of coastlines, erosion of mountains, volcanic eruptions and earthquakes. Attempts to classify geological bodies and describe minerals were in Avicenna and Al-Burini. Currently, some scientists suggest that modern geology originated in the medieval Islamic world. Similar studies in the Renaissance were done by Girolamo Fracastoro and Leonardo da Vinci. They were the first to suggest that fossil shells are the remains of extinct organisms. They also believed that the history of the Earth itself is much longer than the biblical ideas about it. At the end of the XVII century a general theory of the planet arose, which became known as Diluvianism. Scientists of that time believed that the fossils and sedimentary rocks themselves were formed due to the global flood.
Mineral demand very quickly increased already towards the end of the 18th century. Thus, the bowels were studied. Basically, the accumulation of factual materials, descriptions of the properties and characteristics of rocks, as well as studies of the conditions of their occurrence. In addition, observation techniques were developed. For almost the entire nineteenth century, geology was entirely concerned with the question of the exact age of the Earth.Estimated estimates varied quite a lot: from one hundred thousand years to billions. However, the age of the planet was originally determined at the beginning of the 20th century. In many ways, radiometric dating has contributed to this. The estimate obtained then is about 2 billion years. Currently, the true age of the Earth is established. It is approximately 4.5 billion years old.